Telephone apparatus.



PATENTED AUG. 7, 1906 C. A. BUGKLIN. TELEPHONE APPARATUS.

I APPLICATION FILED JULY 3, 1902.

s SHEETS-SHEET 1.

I ATTORNEY PATENTEID AUG. 7, 1906.

0. A. BUGKLIN. TELEPHONE APPARATUS.

APPLICATION FILED JULY 3. 1903.

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- INVENTOR 64% am ATTORNEY RS cm, WASHINGTON, u. c.

No. 828,271. PA-TENTED AUG. 7, 1906.

' O. A. BUOKLIN.

TELEPHONE APPARATUS.

APPLICATION FILED JULY 3, 1903.

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WITNESSES: S INVENTOR 00%, M v a,

. S ATTORNEY in: "arms PETERS co, wnsnmcrou': n c

UNITED STATES PATENT OFFICE.

CHARLES A. BUCKLIN', OF NEW YORK, N. Y., ASSTGNOR TO BARBARA J.

FRANCIS, OF NEW YORK, N. Y.

TELEPHONE APPARATUS.

Specification of Letters Patent.

Patented Aug. 7, 1906.

Application filed July 3, 1903. Serial No. 164.159.

To all whom it uny concern:

Be it known that I, CHARLES A. BUoKLIN, a citizen of the United States, and a resident of the borough of Manhattan, in the city, county, and State of New York, have invented a certain new and useful Improvement in Telephone Apparatus, of which the following is a specification.

This invention is peculiarly applicable to telephones operated on party-lines or to individual or branch telephones operated from a main telephone or switchboard.

It will'be described particularly with respect to its utility upon party-lines. Here, as is well known, a number of instruments, varying from two to four, are commonly mounted in either a grounded or round metallic circuit running from a central station, the circuit therefore passing continuously through all of the instruments on that line. The preliminary impulse or call is commonly transmitted by a pulsating current operating only the bells of the several substations or by a direct current where provision is made at the substation whereby this may affect only such bells.

The great objection to the use of partyline telephones resides in the fact that there can be no privacy of communication, all of the instruments upon such a line being either operative or inoperative. Upon closing the circuit at any instrument or substation the circuit may be cut in upon at any other instrument or substation. Consequently a conversation carried on over the wire from one substation to another or from one substation to a central station may be heard at any of the other substations upon the same line. Means have been heretofore suggested for removing this evil-as, for instance, the employment of a separate conductor or conductors running from the central station or the use of a disabling device at each of the substations operated by high-resistance mag nets. Both of these suggestions are faulty, the former in that the expense of installation is necessarily high and the latter in that the successful operation of the disabling devices is dependent upon the maintenance of a nice balance of the magnets or relaysa thing found practically impossible in the commercial operation of a telephone system.

Under my invention a disabling device is employed located at each of the several substations on a party-line and operable by means of the main circuit. The operation of these disabling devices is controlled at the central station. Each disabling device includes a lock for the telephone-lever, which may be canted upon its hinge (upon the removal of the telephone) only when the disabling device is in inoperative position. Normally all of the disabling devices are in inoperative position to enable the central station to be called from any of the substations. When it is desired to call a substation from the central station, an impulse or series of impulses is transmitted to that station, sounding the bell there located to call the attention of the subscriber. The disabling device being in inoperative position, the supscriber upon removing the telephone from the hook closes the circuit through the instrument and is therebyenabled to respond to the call. Another impulse or series of impulses is then transmitted over the entire party-line from the central station, which throws to operative position the disabling devices located at all substations savethe one in communication with the central station, whereupon each of such other substations is disabled, this being accomplished either magnetically or by the operation of a positive mechanical lock or latch which precludes movement of the telephone-lever (upon removal of the telephone) sufficient to close the circuit at such other substations.

The invention is illustrated in the accompanying drawings, in which Figure 1 is a diagrammatic view showing a main party-line with two substations cone nected thereto. Fig. 2 is a central vertical section of an individual or desk telephone employing a preferred form of my invention. Fig. 3 is a plan view of a portion of the disabling device shown in Fig. 1, hereinafter to be referred to; and Fig. 4 is a diagrammatic view illustrating the arrangement of circuits and apparatus in the central station.

Referring to the drawings, in which similar characters denote corresponding parts, it will be seen that I have selected for the purpose of disclosing the invention a well-known type of desk instrument comprising a standard A, enlarged base B, and telephone C, mounted upon a lever D, hinged at d to the standard as supported upon a block e.

F designates a vertical guide-rod, the upper end of which may be secured in any suitable manner in the longitudinal center of the standard A, the lower end thereof being se' cured (as, for instance, by means of screwthreads and nut f to the supporting-block e.

G designates the armature of the magnets E. This is guarded against lateral displacement relatively to the poles of the magnets E, preferably by means of pins secured to one and having vertical movement in the other. To the armature G is secured a section of tubing H, preferably of insulating material, the exterior of which near its lower end is screw-threaded, whereby it may be rigidly secured to the armature G.

e designates a coil-spring interposed between the supporting-block e and the lower end of the section of tubing H and exerting a tendency to press said tubing, and consequently the armature G, upwardly.

The upper end of the tube-section H is provided with a disk J, havin a dependin flange Preferably this disi is provided with a collar or sleeve j, by means whereof it is secured to the upper end of the tube-sec tion H. The disk J is preferably formed of hard rubber or other insulating material. As here shown, when the circuit is open and the armature therefore under the stress of the coil-sprin e in retracted position the disk J is locate immediately above the point of contact between the shoulder d and contactplate (1 by means whereof the circuit throu h the instrument is closed. Said disk is preferably provided with openings through which the line-wires may be passed in order to connect them with the receiver.

Referring now to the diagrammatic illustration in Fig. 1 illustrating the manner in which the desk instrument above described is connected in the system, L M designate the line-wires of a party-line circuit provided at the central station with batteries L M and, if desired, grounded, as shown. In this main-line circuit and also at the central station is interposed a double-pole switch N. The apparatus and wiring in each of the substations being the same, but one such substation need be described in detail, there being, however, two substations A A diagrammatically illustrated in Fig. 1. The local circuit through the substation is as follows:

A conductor Z runs from the line-wire L to the telephone-lever D, thence, if the hook end of said lever be in its uppermost position, due to the removal of the telephone and the inoperative position of the disabling device, through the transmitter C, and thence back to the line-wire M. The telephone C is in an induced circuit 0, forming part of the local circuit just traced. In the diagrammatic view of Fig.1 this circuit is shown as open at the telephone-lever D, the contact-making shoulder (1 thereof being removed from the contact-plate (P, Fig. 2, by the canting of the lever D, due to the weight of the telephone 0. O designates a branch conductor running from the local circuit-wire l to an armature-lever o, spring-retracted in the usual manner against a stop 0. p designates a conductor running from the branch conductor 0 through a condenser P and thence toa relay P, of which the armature of the lever 0 forms a part. p designates a conductor running from the relay P to a relay R, presently to be described. Q designates a polarized call-bell connected to the conductor p by means of a bell-circuit conductor p connected with a stop p adjacent to the relayarmature 0 and in position to make contact therewith when said armature is drawn to the poles of the relay P. S designates the armature of the relay R, here shown as pivoted at s and provided with a weight s and stop 8 The other end of the armature S is provided with a contact member 8 operating in a mercury-cup 8*, with which is connected the grounded conductor 8 The conductor p after winding upon the relay R is connected with the grounded mercury-cup conductor 8 T designates a conductor running from the pivotal point 8 of the lever S, thence around the core of the relay R, thence to the disabling-magnet E, through the same, and thence through wire t to connection with the conductor from the transmitter C to the line-Wire M. A branch conductor 15 runs from the conductor T through a condenser t thence around the core of the relay R, and thence to the ground. The lockingdisk J is diagrammatically illustrated in Fig. 1 as the armature lever of the disablingmagnet E.

In Fig. 4 I have illustrated a suitable manner of arranging the central-station apparatus, this being commonly practiced in the art at the present time. Here each of the line-wires M and L is connected with a switch-arm V V, coacting, respectively, with contacts 1, 2, 3, and 4 and contacts 5, 6, 7, and 8. vThe central-station line W is preferably grounded (at w) and runs to the contacts 3 and 6. A branch of each side runs to an interrupter X X, and from each of the latter a split conductor runs to the switchcontacts-that from interrupter X running to contacts 2 and 5 and that from interrupter X running to contacts 4 and '7. The interrupter X is adapted to transmit a plus pulsating current and the interrupter X is adapted to transmit a minus pulsating cur-- pulsating current over wire L, the switch V- is thrown to the contact 5, and when it is desired to send a minus pulsating current over wire L the switch V is thrown to contact 7. Likewise when it is desired to send eithera plus or minus pulsating current over the wire M the switch V is moved to either the contact 2 or 4. By this provision it will be seen that a minus or plus pulsating current may be readily sent over either of the linewires by the central-office attendants for the purposes hereinafter described.

The operation of the system herein described is as follows: When the line is not in use, the lock J is in inoperative position, there being no current through the disablingmagnet E. It now it is desired to call a subscriber from the central station, this may be done by means of a pulsating current which will operate only the polarized bell Q at the substation which it is desired to call. If there be but four substations upon the party-line, (and good practice in telephony precludes more,) this may be accomplished by so arranging the four polarized callbells as that two thereof may be operated by current sent over one main-line conductor and the other two by current sent over the other main-line conductor. Then of the two polarized bells operated by one of the main-line conductors one may be so arranged as to re spend only to a plus pulsating call and the other to a minus pulsating call. Thus if it be desired to call the subscriber at the sub station A a minus pulsating call may be transmitted over the line-wire L, which will pass through the local conductor Z, thence (the circuit being open at the instrument) through the condenser P and relay P, thence over the conductor p to the relay R, and thence by way of the mercury-cup conductor .9 to the ground. The energizing of the re lay-magnet P causes the armature 0 to be attracted to thereby send current through the polarized call-bell Q. The energizing of the coil around the relay R and the consequent operation of the mercury-cup contact causes the simultaneous energizing of the disabling-magnet E, (by way of the conductor T,) which thereupon attracts the locking device J to the poles of the magnet E. The pulsating call which operates the polarized bell Q at substation A accomplishes the same result, save the soundlng of the alarm, in'all of the other substations on the l1ne'i. 6., the attraction of the armatures of the disabling-magnets in the other substations and the consequent looking out of the instruments there located. Only the alarm Q at substation A has been sounded. All of the instruments on the line being now disabled, it is necessary to release tne disabling device at substation A in order that the substation subscriber may communicate with the central station. This is done by breaking the circuit at the central station, whereupon the armatures of all the disablingmagnets in the system are thrown to inoperative (retracted) position, at which time a subscriber at any one of the substations may close the circuit through his instrument and communicate with the central station. Only the ,bell Q at substation A having been sounded, however, there is nothing at the other substations to indicate that a connection on the circuit is desired. After the sub-- scrlber at substation A therefore, has removed his telephone from the hook and the lever D has canted upon its hinge, so as to close the circuit through the instrument, as hereinabove set forth, a third operation on the part of the central-stat1on attendant is essential to lock out the other substations of the system. This is accomplished by a repetition of the preliminary pulsating call, which will again operate only the polarized bell Q at substation A the same impulse or series of impulses being transmitted to the other substations, but, due to the arrange ment of the polarized bells hereinabove de scribed, not sounding the alarms at such other substations. All of the disablingmagnets at those stations are, however, en-- ergized in order to attract their armatures, and thereby prevent the circuit from being closed through such substations by the canting of the telephone-levers upon their hinges.

While the preliminary pulsating call to which I have referred may be relied upon to operate the disabling-magnets of all of the substations with which it is not desired to communicate, it is obvious that when this pulsating call has terminated and current thereby cut off through the disabling-magnets additionalprovision must be made for maintaining the electrical energy of said magnets. This is accomplished by the mercury-cup relay hereinabove described, which bridges over the interval between the cessation of the pulsating call and the application of the constant current through each of the substations. Thus the second pulsating call has operated at all of the substations other than A to close the mercury contact and to thereby maintain the energy of the disablingmagnets E at such substations through the constant current from the line-wires L M, the circuit being from the line-wire M through the disabling-magnets E, thence through the 0011- ductor T to the core of the relay R, thence to the lever S and contact member 8 through the mercury-cup, and thence through the conductor 8 to the ground. This energizing of the disabling-magnets E by maintaining the attracted position of the armature-locks prevents the telephone-levers D from being sufficiently canted on their hinges to close the circuit at all of the substations with which it is not desired to communicate. The

. hook both that substation, as well as all of the other substations on the main line, are thrown into their normal operative position by the opening of the circuit at the central station. Due to this the mercury-cup contact is broken, all of the disabling-magnets E denergized, and all of their armatures retracted under the stress of their retractingsprings.

It is obvious that in place of the mercurycup contact herein shown and described a relay of other form may be employed to enable the constant current to pass through the disabling-magnets E. Thus, for instance, a balance-relay may be employed normally inoperative, but operated under the influence of the pulsating call to close the circuit between a disabling-magnet E and either the ground or return conductor, preferably the former.

If it be desired to communicate to the central station from one of the substations, the line being in its normal condition, in which noneof the instruments is locked out, the subscriber at substation A (for instance) may remove his telephone from the hook, where upon the circuit will be closed at such hook to place him in communication with the central station. In order that he may have un-' interrupted use of the line and the other substations be locked out, the call-bell Q (at substation A is sounded by means of the pulsating call, which, as hereinabove described, operates all of the disabling-magnets in the other substations, and particularly the mercury-cup or equivalent relay, which, after such disabling-magnets have been energized by the pulsating call, permits the energizing of these magnets to be continued by the constant current from the line. Under this condition the proper connection may be readily made at the central station, giving the subscriber at substation A complete control. Should the subscriber at substation A wish to communicate with the subscriber at substation A he may proceed, as before explained, to call up the central-station attendant, who will in turn call up A subscriber. When both are at their telephones, all other substations to be locked out.

instruments on the same circuit may readily be disabled by the central-station attendant in the manner above described.

When there are four substations employed and it is desired to connect the substation A with either of the substations connected with the line-wire L, central will first call up substation A which will cause the other three Central then operates her switch to release all of the substations and calls up the substation connected to line-wire M, with which it is desired to connect substation A each individual as he is called leaving his receiver oil the hook until the conversation is finished.

In order that the subscribers at the substations may be informed as to the condition of the circuit in which their instruments are includedt. 6., as to whether that circuit is in use or not-I may, if desired, provide each of the instruments with a visual indicator of any suitable form and operated either magnetically or mechanically. This may be done conveniently by causing the armature of the disabling-magnet to operate a slide discernible through a slot in the casing of the transmitter and which will show white to indicate that the line is not in use and red to show that it is being used at some other substation. This visual indicating mechanism forming no part of the present invention is not illustrated herein.

Having now described my invention, what I claim as new'therein, and desire to secure by Letters Patent, is as follows:

1. In telephone apparatus, the combination with a central station, a main circuit running therefrom, and a substation mounted in a normally op en circuit communicating with said main circuit, of a branch circuit around said normally 0 en substation-circuit, a disabling device an a bell mounted insaid branch circuit, both being operated from the central station, and a relay, also in said branch circuit, coacting with said disabling device to hold the same in operative position after said device has been thrown to such position from the central station, substantially as set forth.

2. In telephone apparatus, the combination with a central station, a main circuit comprising two grounded metallic conductors running therefrom, and a substation mounted in a normally open circuit connected with said main circuit, of a grounded branch circuit connected with said normally open circuit, a disabling device operated by said grounded branch circuit, and a relay mounted in said grounded branch circuitfor maintaining said disabling device in operative position, substantially as set forth.

3. In telephone apparatus, the combination with a central station, a main circuit comprising two metallic conductors running therefrom and a substation mounted in a normally open circuit connected with said main circuit, of a branch circuit connected with said normally open circuit, a disabling device operated by said branch circuit, and a slowacting circuit-changing device in said branch circuit and coacting with said disabling device to maintain the same in operative position, substantially as set forth.

4. In telephone apparatus, the combination with a central station, a main circuit comprising two metallic conductors running therefrom, a series of substations each mounted in a normally open circuit connected with said main circuit, and disabling devices for said substations mounted in branch circuits connected therewith, of means for throwing said disabling devices to operative position from the central station, and provision, auxiliary to said disabling device and operative after the cessation of the initial current-change in the circuit from the central station, for maintaining said device in operative position, substantially as set forth.

5. In telephone apparatus, the combination with a central station, a main circuit comprising two metallic conductors running therefrom, a series of substations each mounted in a normally open circuit connected with said main circuit, and disabling devices for said substations mounted in branch circuits connected therewith, of means operable from the central station for cutting out all of said substations and simul' taneously sounding a call at one thereof, and for releasing all of said stations after sounding said call and then again cutting out all substations save that at which such call has been sounded -upon response from the station called, such means including a, slow-acting current-changing device cooperating with the disabling device in each substation to maintain the same in operative position after the cessation of the impulse from the central station first above named, substantially as set forth.

This specification signed and witnessed this 16th day of June, 1903.

CHARLES A. BUOKLIN.

Witnesses:

S. O. EDMONDS, R. BEACH FERNHEAD. 

